Research On Constant Strain Rate Control Technology Of 200MN Isothermal Forging Hydraulic Press

The titanium alloy isothermal forging hydraulic press is a hard-deforming-material forming equipment and a heavy machinery engineering equipment which is necessary for the manufacture of aviation high performance parts.200 MN isothermal forging hydraulic machine is an advanced heavy engineering equipment which consists of machinery,hydraulic system and electrical control system.It can complete large upsetting,die forging blank,rough blank,pre molding and correction of the excellent material.Focusing on the latest 200 MN isothermal forging hydraulic press applied to the domestic manufacture and aviation forging industry,this paper concerns the thorough theory and the application realization of the deforming constant strain rate control of the hard-deforming alloys,such as the titanium alloy and high temperature alloy,during superplastic forging.Firstly,the control system model is established.By analysing the structure and working principle of the isothermal forging hydraulic machine,combined with the characteristics of valve controlled hydraulic cylinder system,the mathematical model of constant strain rate control is created.Using the Simulink toolbox of Matlab software,the control model system is establshed.Furthermore,the control strategy and simulation analysis are designed.The Simulink controller module which uses the fuzzy PID control algorithm are designed and built,and the fuzzy inference system editor is adapted to adjust the parameters of the controller.The load pressure ramp signal is used as the input signal to adjust the PID control parameters continuously.Then the fuzzy control rules are obtained.Finally,the test.Considering the complexity of the hydraulic system,the hardware characteristics of electronic control system and controller operation ability,the hardware control system and the program of the 200 MN isothermal forging hydraulic machine is designed,According to the fuzzy control rules,the fuzzy PID controller is established.After the field test,the author compares the obtained results with the results of the simulation.This paper is a research of the application of constant strain control for large-scale isothermal forging hydraulic press.Using the fuzzy control and the speed closed-loop control theory and combining with the theoretical research,simulation analysis and the field test,the constant strain control in the forming process of large titanium alloy and high temperature alloy has been realized,which has improved the production capacity of large die forging.Meanwhile,the research acts as the reference for the application of electro hydraulic servo control strategy for the isothermal forging hydraulic press.